Egypt's ruling military has said that it will impose an overnight curfew on in Cairo's defence ministry district for a second successive night after deadly clashes with protesters.

A military official told the AFP news agency that the curfew will go into effect between 11 pm local time (2100 GMT) on Saturday and 6 am (0400 GMT) on Sunday.

The military has also ordered 300 people detained over deadly clashes between troops and anti-military protesters.Military prosecutors said the 300, including nine journalists, "will be held for 15 days pending investigation" into clashes on Friday that left two people including a soldier dead and at least 373 injured.

Hundreds of troops guarding the ministry surged forward earlier on Friday when protesters began cutting through barbed wire used to seal off the ministry building, in the central Abbasiya neighbourhood.

Tensions have been running high after 11 people were killed in clashes that broke out on Wednesday when unidentified assailants fired at protesters staging a sit-in outside the defence ministry building.

Plastered with posters

In the run-up to Friday's rally, political activists had plastered Cairo's Tahrir Square with banners reading, "Down with military rule".

"I’m telling the military council… enough bloodshed, enough fabricated crisis, enough unleashing of thugs on the public, enough destruction… we want them to transfer power to an independent transitional authority tomorrow,” Akrami Darwish, a protester, said on Friday.

Several pro-democracy movements, including April 6, as well as the Muslim Brotherhood, had said they would be joining the protests in Cairo and the Mediterranean city of Alexandria.

The ultra-conservative Salafi movement, which has become increasingly popular recently, also participated in the rallies.

"If anyone approaches its [installations], they should hold themselves responsible," General Mulla said on Thursday.

Handover of power

Soldiers have been accused of standing idly by near Wednesday's clashes outside the defence ministry and not intervening until after the deaths of some of the protesters.

However, the army denied that it was responsible for the bloodshed.

"Our hands are clean of Egyptian blood," Major General Mohammed al-Assar said on Thursday.

The SCAF has tried to counter accusations that it might use the violence as a pretext to ignore its own deadline to relinquish control of the country.

Presidential elections are scheduled for May 23 and 24 and a run-off for June 16 and 17 if there is no outright winner in the first round.

"We say it frankly and clearly. The armed forces and their supreme council are committed to the handover of power on June 30," Assar said.

"We don't desire power. The Supreme Council is not a substitute for legitimacy in Egypt."

He said the military would ensure the integrity and fairness of the presidential election.

"We are committed to fair elections," Assar said. "We don't have any [favoured] candidates. All the candidates are respectable Egyptians."

The military has said it would hand over power to civilian rule before the end of June, or by May if there is a clear winner in the first round of elections.